Remove ES_NEXT macro (#4915)

- remove all '#JERRY_ESNEXT' macro
- remove 5.1 build profile, update test runner accordingly (Note: all builtins are turn on by default)
- move tests from tests/jerry/esnext into tests/jerry, concatenate files with same names
- add skiplist to some snapshot tests that were supported only in 5.1
- fix doxygen issues that were hidden before (bc. of es.next macro)

Co-authored-by: Martin Negyokru negyokru@inf.u-szeged.hu
JerryScript-DCO-1.0-Signed-off-by: Adam Szilagyi aszilagy@inf.u-szeged.hu

jerry-core/ecma/builtin-objects/ecma-builtins-internal.h

@@ -31,12 +31,10 @@ typedef enum
   ECMA_BUILTIN_PROPERTY_SIMPLE, /**< simple value property */
   ECMA_BUILTIN_PROPERTY_NUMBER, /**< number value property */
   ECMA_BUILTIN_PROPERTY_STRING, /**< string value property */
-#if JERRY_ESNEXT
   ECMA_BUILTIN_PROPERTY_SYMBOL, /**< symbol value property */
   ECMA_BUILTIN_PROPERTY_INTRINSIC_PROPERTY, /**< intrinsic routine property */
   ECMA_BUILTIN_PROPERTY_ACCESSOR_BUILTIN_FUNCTION, /**< full accessor property with builtin function object
                                                         getter/setter pair */
-#endif /* JERRY_ESNEXT */
   ECMA_BUILTIN_PROPERTY_OBJECT, /**< builtin object property */
   ECMA_BUILTIN_PROPERTY_ROUTINE, /**< routine property */
   ECMA_BUILTIN_PROPERTY_ACCESSOR_READ_WRITE, /**< full accessor property */
@@ -51,11 +49,9 @@ typedef enum
 {
   ECMA_BUILTIN_NUMBER_MAX = 256, /**< value of ECMA_NUMBER_MAX_VALUE */
   ECMA_BUILTIN_NUMBER_MIN, /**< value of ECMA_NUMBER_MIN_VALUE */
-#if JERRY_ESNEXT
   ECMA_BUILTIN_NUMBER_EPSILON, /**< value of ECMA_NUMBER_EPSILON */
   ECMA_BUILTIN_NUMBER_MAX_SAFE_INTEGER, /**< value of ECMA_NUMBER_MAX_SAFE_INTEGER */
   ECMA_BUILTIN_NUMBER_MIN_SAFE_INTEGER, /**< value of ECMA_NUMBER_MIN_SAFE_INTEGER */
-#endif /* JERRY_ESNEXT */
   ECMA_BUILTIN_NUMBER_E, /**< value of ECMA_NUMBER_E */
   ECMA_BUILTIN_NUMBER_PI, /**< value of ECMA_NUMBER_PI */
   ECMA_BUILTIN_NUMBER_LN10, /**< value of ECMA_NUMBER_LN10 */